Boston Marathon Bomber Convicted On All Counts

Boston Marathon bomber Dzhokhar Tsarnaev has been convicted on all 30 federal charges he faced in connection with the deadly attacks.

The 21-year-old did not react as the jury read out the guilty verdicts in front of victims' relatives and survivors of the 15 April 2013 bombings that killed three people and injured 264 others.

Tsarnaev also was found guilty of the fatal shooting of MIT police officer Sean Collier.

Seventeen of the 30 charges, including conspiracy and use of a weapon of mass destruction, carry a possible death sentence.

Jurors will determine sentencing upon completion of a penalty phase, during which the panel will hear additional testimony.

The defence has not indicated whether Tsarnaev will take the stand during the second phase of the trial.

His attorneys acknowledged at the trial's outset that he carried out the attacks with his older brother Tamerlan Tsarnaev, who was killed following a gun battle with police.

Jurors took a little more than 11 hours over the course of two days to reach a verdict. The panel's decision came one week before the bombings' second anniversary.

Family members of victims, along with survivors of the attacks, remained quiet as the verdict was read in court.

Krystle Campbell, 29, Lingzi Lu, 23, and eight-year-old Martin Richard were killed in the bombings.

Martin's father, Bill Richard, embraced one of the prosecutors after the proceedings ended.

Karen Brassard, who was injured in the attacks, spoke on behalf of fellow victims outside the court, telling reporters that while they were "grateful for the outcome", the guilty verdict did not necessarily bring closure.

"It's not something that'll ever be over. You'll feel it forever," she said. "It's forever a part of our lives."

Transit police officer Dic Donohue, who was wounded on the night his close friend Officer Collier was killed, praised the verdict on Twitter.

"Although we cannot change the past, including the loss of a friend and fellow police officer, justice has been served today," he wrote.

Boston Police Commissioner William Evans said in a statement he was "glad for the victims' families and the survivors" that the judicial process was coming to a close

"Today's verdict will hopefully give some peace to those affected by the horrific acts of the defendant," he said.

During the trial, the defence sought to spare Tsarnaev the death penalty by attempting to convince jurors he was pressured into carrying out the attacks by his radicalised brother.

Over the course of several weeks, the jury heard testimony from friends and family of those killed and from more than a dozen people who lost limbs as a result of the bombings.

The panel even heard from police officers who described exchanging gunfire and dodging homemade explosive devices thrown by the Tsarnaev brothers as they attempted to flee the city.

In closing arguments, the prosecution said Tsarnaev, an ethnic Chechen, wanted to "punish America" for its wars in Muslim countries.

Prosecutors showed the court images of a blood-stained message Tsarnaev scrawled on the inside of a boat, where he was found hiding days after the attacks.

The bullet-riddled message said: "The US Government is killing our innocent civilians but most of you already know that.

"As a M (bullet hole) I can't stand to see such evil go unpunished, we Muslims are one body, you hurt one you hurt us all.

"Now I don't like killing innocent people it is forbidden in Islam but due to said (bullet hole) it is allowed."

The defence, which called just four witnesses in presenting its case, said in closing arguments that evidence showed Tamerlan Tsarnaev was the leader of the plot.

"Tamerlan built the bombs, Tamerlan murdered Officer Collier, Tamerlan lead and Dzhokhar followed," defence attorney Judith Clarke said.

Ms Clarke is one of America's foremost death-penalty attorneys. She successfully saved Unabomber Ted Kaczynski and Susan Smith, who drowned her two children in a lake in 1994.